1. Field of the Invention
This invention relates to a train of railway cars and, more particularly, to an articulated coupling between two railway cars or vehicles that are positioned on a median, or intermediate, truck. The articulated coupling is formed or constructed of resilient or elastomeric elements.
2. Background Information
An articulated connection between railway cars or vehicles in articulated trains, where two ends of the cars or vehicles rest on a single median or intermediate truck, may employ a rounded or spherical ball and socket joint to link one vehicle to the other vehicle. One of the vehicles may have a portion of the joint positioned around a portion of the joint of another vehicle to, thereby, control the roll between the two vehicles. Such articulated couplings support a high load by means of an elastomeric mechanism that is sandwiched between armatures. The articulated couplings employ intermediate armatures such as hoops, and the assembly of elastomeric elements and hoops may be prestressed as necessary. Therefore, they require a great deal of machining and cost a great deal to manufacture on account of their significant rigidity, even though they provide rather low anti-vibration filtering.
French Patent having Publication No. 2,357,409 and Patent No. 76 20867 to SOCIETE GENERALE DE CONSTRUCTIONS ELECTRIQUES ET MECANIQUES ALSTHOM recites several separate articulations around two vertical axes and a horizontal axis. The articulations are all integrated with a gangway compartment. This arrangement may be employed if the bodies of two adjacent vehicles are roll-linked by a system employing universal joints.
With this arrangement, the elastomer mechanism which bears the vehicle load, or weight, is limited to rotations around one, or possibly both, vertical axes connecting one vehicle body and one-half of the gangway compartment. The execution of the angular movement between the two vehicles requires only one-half of the angle between the vehicles, since the compartment, which is positioned on the median truck, bisects the angle by its horizontal axis. Under these circumstances, consequently, the articulation needs to provide only limited performance requirements. However, such is not the case for a train with more than two successive vehicles, because no rolling flexibility or track distortion separates them. Therefore, the device disclosed in this patent is limited to tramways or self-propelled trains having two inseparable bodies.
French Patent having Publication 2,631,917 and Patent No. 88 06878 to SOCIETE GENERALE DE CONSTRUCTIONS ELECTRIQUES ET MECANIQUES ALSTHOM discloses a device that is satisfactory for use in a long train. The joint between vehicles, or cars, includes an annular portion with a truncated conical surface. Also provided is an enveloping support piece that is connected to one of the vehicles of the train. The joint also includes an annular articulation element that is made of resilient or elastomer composite material. The joint further includes metal plates that are positioned between layers of elastomeric material and the joint is surrounded by and in contact with the external truncated conical surface. This patent publication also discloses an alternate embodiment in which the metal plates and the layers of resilient material have the shape of a spherical sector.